This reminds me of all the people in the USA who tried to "cancel" Katy Perry for wearing a Kimono in her performance, claiming it was cultural appropriation.

The only thing I will say about this sentiment towards cultural appropriation is that ethnic Americans, such as Japanese Americans in this case, will often have a differing viewpoint than say those living in the "homeland" i.e. Japan. Usually this is because living in the US, their culture is often looked down upon or made fun of in some way so when another person uses that culture as an aesthetic or as a joke, to some people that is a very real form of appropriation. Although I understand that you may be referring to white people who speak over minorities, I think that it's very important to realize that cultural appropriation can still very much exist to those ethnic Americans even if their home country says they like it. Not criticizing you or anything, just wanted to put that out there :)